From 88adf888803f05ab5af6a69c4b0e710eb86bde6d Mon Sep 17 00:00:00 2001
From: Patrick Gaskin <patrick@pgaskin.net>
Date: Mon, 25 May 2020 17:17:27 -0400
Subject: [PATCH] Implemented skip action (closes #31) (#32)

---
 res/doc        | 14 ++++++++------
 src/action.h   |  7 +++++--
 src/action_c.c | 16 ++++++++++++++++
 src/menu.cc    | 20 ++++++++++++++++++--
 4 files changed, 47 insertions(+), 10 deletions(-)

diff --git a/res/doc b/res/doc
index 6b4fc99..ab86cc0 100644
--- a/res/doc
+++ b/res/doc
@@ -20,6 +20,8 @@
 #                   reader - the overflow menu in the reader
 #     <label>     the label to show on the menu item (must not contain :)
 #     <action>    the type of action to run, one of:
+#                   cmd_spawn      - starts another process or script in the background
+#                   cmd_output     - runs a command and displays the output
 #                   dbg_syslog     - writes a message to syslog (for testing)
 #                   dbg_error      - always returns an error (for testing)
 #                   dbg_msg        - shows a message (for testing)
@@ -29,9 +31,12 @@
 #                   nickel_extras  - opens one of the beta features
 #                   nickel_misc    - other stuff which isn't significant enough for its own category
 #                   power          - gracefully controls the power state
-#                   cmd_spawn      - starts another process or script in the background
-#                   cmd_output     - runs a command and displays the output
+#                   skip           - skips a number of actions after the current one (mainly useful for more complex conditional chains) (this action will not update the success/failure flag)
 #     <arg>       the argument passed to the action:
+#                   cmd_spawn      - the command line to pass to /bin/sh -c (started in /)
+#                                    It can be prefixed with "quiet:" to prevent the toast with the process PID from being displayed.
+#                   cmd_output     - the timeout in milliseconds (0 < t < 10000), a colon, then the command line to pass to /bin/sh -c (started in /)
+#                                    It can be prefixed with "quiet:" to prevent the message box with the output from being displayed (i.e. you'd use this where you'd normally use >/dev/null 2>&1).
 #                   dbg_syslog     - the text to write
 #                   dbg_error      - the error message
 #                   dbg_msg        - the message
@@ -58,10 +63,7 @@
 #                   power          - one of:
 #                                      shutdown (4.13.12638+)
 #                                      reboot (4.13.12638+)
-#                   cmd_spawn      - the command line to pass to /bin/sh -c (started in /)
-#                                    It can be prefixed with "quiet:" to prevent the toast with the process PID from being displayed.
-#                   cmd_output     - the timeout in milliseconds (0 < t < 10000), a colon, then the command line to pass to /bin/sh -c (started in /)
-#                                    It can be prefixed with "quiet:" to prevent the message box with the output from being displayed (i.e. you'd use this where you'd normally use >/dev/null 2>&1).
+#                   skip           - the number of actions to skip, or -1 to skip all remaining ones (i.e. end the chain)
 #
 #   chain_success:<action>:<arg>
 #   chain_failure:<action>:<arg>
diff --git a/src/action.h b/src/action.h
index 6b1bc3f..c75b6ab 100644
--- a/src/action.h
+++ b/src/action.h
@@ -8,11 +8,13 @@ typedef enum {
     NM_ACTION_RESULT_TYPE_SILENT = 0,
     NM_ACTION_RESULT_TYPE_MSG    = 1,
     NM_ACTION_RESULT_TYPE_TOAST  = 2,
+    NM_ACTION_RESULT_TYPE_SKIP   = 3, // for use by skip only
 } nm_action_result_type_t;
 
 typedef struct {
     nm_action_result_type_t type;
     char *msg;
+    int skip; // for use by skip only
 } nm_action_result_t;
 
 typedef nm_action_result_t *(*nm_action_fn_t)(const char *arg, char **err);
@@ -31,6 +33,8 @@ void nm_action_result_free(nm_action_result_t *res);
 #endif
 
 #define NM_ACTIONS    \
+    X(cmd_spawn)      \
+    X(cmd_output)     \
     X(dbg_syslog)     \
     X(dbg_error)      \
     X(dbg_msg)        \
@@ -41,8 +45,7 @@ void nm_action_result_free(nm_action_result_t *res);
     X(nickel_extras)  \
     X(nickel_misc)    \
     X(power)          \
-    X(cmd_spawn)      \
-    X(cmd_output)
+    X(skip)
 
 #define X(name) NM_ACTION_(name);
 NM_ACTIONS
diff --git a/src/action_c.c b/src/action_c.c
index 3cc4f4c..47c0725 100644
--- a/src/action_c.c
+++ b/src/action_c.c
@@ -1,4 +1,5 @@
 #define _GNU_SOURCE // asprintf
+#include <limits.h>
 
 #include "action.h"
 #include "kfmon.h"
@@ -29,6 +30,21 @@ NM_ACTION_(dbg_toast) {
     #undef NM_ERR_RET
 }
 
+NM_ACTION_(skip) {
+    #define NM_ERR_RET NULL
+
+    char *tmp;
+    long n = strtol(arg, &tmp, 10);
+    NM_ASSERT(*arg && !*tmp && n != 0 && n >= -1 && n < INT_MAX, "invalid count '%s': must be a nonzero integer or -1", arg);
+
+    nm_action_result_t *res = calloc(1, sizeof(nm_action_result_t));
+    res->type = NM_ACTION_RESULT_TYPE_SKIP;
+    res->skip = (int)(n);
+    NM_RETURN_OK(res);
+
+    #undef NM_ERR_RET
+}
+
 NM_ACTION_(kfmon_id) {
     // Start by watch ID (simpler, but IDs may not be stable across a single power cycle, given severe KFMon config shuffling)
     int status = nm_kfmon_simple_request("start", arg);
diff --git a/src/menu.cc b/src/menu.cc
index 958c9a0..578522f 100644
--- a/src/menu.cc
+++ b/src/menu.cc
@@ -146,16 +146,25 @@ extern "C" MenuTextItem* _nm_menu_hook(void* _this, QMenu* menu, QString const&
             NM_LOG("item '%s' pressed...", it->lbl);
             char *err = NULL;
             bool success = true;
+            int skip = 0;
             for (nm_menu_action_t *cur = it->action; cur; cur = cur->next) {
                 NM_LOG("action %p with argument %s : ", cur->act, cur->arg);
-                NM_LOG("...success=%d ; on_success=%d on_failure=%d", success, cur->on_success, cur->on_failure);
+                NM_LOG("...success=%d ; on_success=%d on_failure=%d skip=%d", success, cur->on_success, cur->on_failure, skip);
+                if (skip) {
+                    NM_LOG("...skipping action due to skip flag (remaining=%d)", skip);
+                    if (skip > 0)
+                        skip--;
+                    continue;
+                }
                 if (!((success && cur->on_success) || (!success && cur->on_failure))) {
                     NM_LOG("...skipping action due to condition flags");
                     continue;
                 }
                 free(err);
                 nm_action_result_t *res = cur->act(cur->arg, &err);
-                if (!(success = err == NULL)) {
+                if (err == NULL && res && res->type == NM_ACTION_RESULT_TYPE_SKIP) {
+                    NM_LOG("...not updating success flag (value=%d) for skip result", success);
+                } else if (!(success = err == NULL)) {
                     NM_LOG("...error: '%s'", err);
                     continue;
                 } else if (!res) {
@@ -178,6 +187,13 @@ extern "C" MenuTextItem* _nm_menu_hook(void* _this, QMenu* menu, QString const&
                     }
                     MainWindowController_toast(mwc, QLatin1String(res->msg), QStringLiteral(""), 1500);
                     break;
+                case NM_ACTION_RESULT_TYPE_SKIP:
+                    skip = res->skip;
+                    if (skip == -1)
+                        NM_LOG("...skipping remaining actions");
+                    else
+                        NM_LOG("...skipping next %d actions", skip);
+                    break;
                 }
                 nm_action_result_free(res);
             }